High
N.089 on Vaillant ecoTEC plus Combi

Your boiler has detected that the internal water pump is not the correct type for your specific model, preventing the system from circulating water properly.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

The installed heating pump does not match the unit type.

From this model's manual
Verified against the Vaillant Ecotec Plus installation & service manual, page 93.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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